New research reveals fresh insights into the role of karst in the Chalk aquifer
New research has thrown fresh light on what scientists understand about the role of karst in the Chalk aquifer, which provides public water supplies to millions of people, agriculture and industry, and sustains vital habitats.20/12/2021 By BGS Press
New research has thrown fresh light on what scientists understand about the role of karst in the Chalk Group aquifer, which provides public water supplies to millions of people, agriculture and industry, and sustains vital habitats. A study led by BGS, published in the Geological Society of London Special Publication SP517, The Chalk Aquifers of Europe, has compiled evidence showing that karst and rapid groundwater flow are much more widespread in the Chalk than previously thought.
The study will be of particular interest for regulators and water companies, both globally and in the UK, when planning future approaches to groundwater source protection and catchment management. Existing research shows that globally, around 20 to 25 per cent of people rely on karst groundwater for supply.
What is karst?
‘Karst’ is a geomorphological term that is applied to a type of landscape where erosion caused by dissolution, in other words the dissolving of bedrock, has resulted in fissures, sinkholes, sinking streams, ridges, caves, springs and other characteristic features. It is typically associated with soluble rock types such as limestone, marble and gypsum.
The Chalk is an unusual karst aquifer with limited cave development, but extensive networks of smaller solutional conduits and fissures that enable rapid groundwater flow. Small-scale karst features such as dolines, stream sinks, dissolution pipes and springs, are common.
This research is the culmination of many years work and is a step forward in our understanding of the Chalk aquifer. Our research presents evidence of the extent of karst in the Chalk throughout England, including almost 100 tracer connections demonstrating rapid groundwater flow.
We found high densities of stream sinks, and karstic conduits, springs, dolines and dissolution pipes are common.
We demonstrate that rapid groundwater flow and karst occur much more frequently than previously thought, which provides an important step forwards in our conceptual understanding of the Chalk and of global karst aquifers more generally.
Our work examines the implications of karst in the Chalk for groundwater protection and demonstrates how the evidence for karst should be central to future strategies for groundwater protection and management.
Louise Maurice, BGS Senior Hydrogeologist and lead author of the study.
Improved understanding of Chalk karst will expand understanding of similar karst aquifers with limited cave development that are globally widespread and provide vital public water resources to millions of people.
Such insights into the unique nature of Chalk karst may also help to advance understanding of classical karst aquifers, where major caves are often the main focus of research and fissures or smaller conduits are less understood.
The full study is titled Karst hydrogeology of the Chalk and implications for groundwater protection. The work is funded by the NERC knowledge Exchange fellowship scheme.
Other work in the Geological Society of London special publication also highlights the importance of karst in the Chalk, including a further BGS-led study, The genesis and evolution of karstic conduit systems in the Chalk.
Dr Marie Cowan awarded the Energy Group Medal by the Geological Society
This award is presented annually to individuals with a geoscience background who have made an outstanding contribution to the energy industry.
BGS appoints new members to Science Advisory Committee
Four new members’ three-year terms begin in June 2023.
AGS file utilities tool: production release
BGS’s online tool for validating AGS files against the official AGS data format rules and its own NGDC data submission requirements goes live.
BGS releases 10K maps through updated maps portal
BGS releases an updated maps portal, which allows users to view all publicly available, maps and includes 10 000 and 1:10 560 scale maps for the first time.
BGS maps out priorities with five-year strategy
BGS publishes its new strategy for 2023 to 2028, ‘Understanding our Earth’.
Improvements to borehole delivery
BGS releases improvements to its borehole layer on the GeoIndex, which makes access faster and improves quality.
Report identifies areas of the UK prospective for critical raw materials
Areas from the Highlands to south-west England have the right geology to be prospective for several critical raw materials such as lithium and graphite, according to a new report.
World Mineral Production 2017 to 2021 is now available
The latest edition of World Mineral Production has been released.
How does public water use influence the amount of phosphorus in the environment?
New research looks at how phosphorus accumulates in public water systems in the USA.
Scientists discover regions of the UK with greatest potential to use heat from deep thermal waters
BGS geologists have mapped the UK’s potential to use heat from thermal groundwater deep beneath central and southern Britain.
BGS laboratories become first in UKRI to receive gold LEAF accreditation
BGS achieved gold certification in the Laboratory Efficiency Assessment Framework (LEAF) accreditation in March 2023.
World Water Day 2023: groundwater photo stories
A showcase of groundwater use from around the world highlighting how developing groundwater has benefited the lives of many people.